To determine the amount of oxalic acid in rhubarb, you chop up and extract 85.2 grams of homogenized rhubarb with hot water. The extract is treated with calcium hydroxide and you isolate 0.6914 grams of solid CaC2O4•H2O.

Question

How many grams of oxalic acid were present in the rhubarb extract?

This is what I had: C2H2O4= 90.04g/mol
85.2g/1•1mol/90.04g= .9462g

Answer 1

mols CaC2O4.H2O = grams/molar mass = 0.6914 g/molar mass CaC2O4.H2O

1 mol CaC2o4.H2O = 1 mol H2C2O4 so multiply mols CaC2O4 x molar mass H2C2O4